Popularity and adjacency based prefetching for efficient IPTV channel navigation

As Internet Protocol Television (IPTV) is becoming increasingly popular, users can enjoy a variety of contents from hundreds of IPTV channels. However, the increased number of channels makes users even more difficult to find their desired contents. Along with this problem, the channel zapping time of IPTV incurs serious user-perceived latency. To alleviate these problems, this paper presents a new channel prefetching scheme that can be implemented on the IPTV set-top box. The scheme basically fetches the contents of adjacent channels before they are actually requested, similar to the adjacency-based prefetching scheme. However, it differentiates the number of channels to be prefetched among up-direction and down-direction channels based on the popularity of channels. Trace-driven simulations with various experimental conditions show that the proposed prefetching scheme performs better than existing prefetching schemes in terms of the prefetching hit rate to find the desired channel. Specifically, when the number of IPTV channels is 150, the average improvement of the hit rate is 22.3% compared to the adjacency-based prefetching scheme.